BP tightens valves to end leak

This still image from a live BP video feed shows oil gushing from a leaking BP oil wellpipe Tuesday. Photo:AFP

Oil giant British Petroleum (BP) hoped Tuesday to finally stem the catastrophic flow of toxic crude in the Gulf of Mexico as it tested a new tighter-fitting cap attached to the gushing well.

The test, according to BP, will last from six to 48 hours "or more, depending on the measurements that are observed," said Admiral Thad Allen, a former Coast Guard chief who is leading the US government's response to the crisis, according to AFP.

Robotic submarines earlier pierced the near darkness 1.6 kilometers down on the sea floor with special lights and relayed live pictures of the operation that could mark the beginning of the end of the 13-week disaster.

With the "Top Hat 10" attached to the leaking pipe, engineers aim next to close valves on the gigantic 75-ton system and start taking readings as its pressure sensors bear the full brunt of the massive gusher.

"It is expected, although cannot be assured, that no oil will be released to the ocean for the duration of the test," BP said, adding, however, that that would not indicate whether the flow had permanently stopped.

If the pressure readings are high enough, BP officials said that the valves will be kept shut, effectively sealing the well.

If they are too low, that would indicate a leak somewhere in the casing of the well, which extends four kilometers below the sea floor.

"We need to make sure that the flow can't come around the well bore rather than through the well bore," BP's chief operating officer, Doug Suttles, said.

The International Energy Agency estimated Tuesday that 2.3-4.5 million barrels of crude have gushed into the sea since the BP-leased Deepwater Horizon sank April 22, two days after a deadly explosion, AFP reported.

The disaster has cost BP some $3.5 billion, although its shares rose sharply Mon-day on reports that it was poised to sell some assets.

"We are in discussions with a number of companies about a number of assets. Talks are going well," spokeswoman Sheila Williams said in London, declining to give de-tails, according to Reuters.

Separately, Reuters quoted experts as saying that some marine life thrives on oil bubbling up naturally from the seabed, even though it cannot cope with giant sin-gle leaks like the one from BP's ruptured well.

Agencies